JPS60186691A - Heat exchanger - Google Patents

Abstract

PURPOSE:To decrease unevenness of cooling and prevent generation of deflection of flow, by a method wherein plural concentric type passes are shaped, and changing the total cross-sectional area of heat transmitting pipes of each pass by turns wherein high viscosity fluid of which viscosity largely changes is heated or cooled. CONSTITUTION:While making the center of pipe group at the entrance 1 side as reference, to- be-cooled fluid enters only from apart of pipe group 2a of preset numbers within the whole pipes (1 pass). The fluid which run out from the pipe group 2a at the outlet side is inverted by 180 deg. and enters into a pipe group 2b (2 passes) at the outer periphery of the pipe group 2a with more numbers at a constant ratio than the numbers of the pipe group 2a from which the fluid runs out (when the fluid within pipes are heated, numbers of pipe become few by the preset ratio). The fluid returned to the entrance 1 side is again inverted by 180 deg. and enters into a pipe group 2c (3 passes) at the outer periphery of the pipe group 2b with more numbers at the preset ratio than the pipe group 2b from which the fluid runs out, and flows out from an outlet 3. In the meantime, heat medium flows into from an entrance 4 and flows out from an exit 5.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-tubular heat exchanger or reactor for heating or cooling a highly viscous fluid whose viscosity changes significantly with changes in temperature and the influence of shear force. .

Conventional poly? 11. An example of a heat input exchanger is shown in Figure 1.

In Figure 1, the fluid to be heat exchanged flows in from population 1, is heated (or cooled) in heat transfer tube 2 by heat transfer from the tube wall, and flows out from number 3, while the heat medium flows from population 4. It flows in and flows out from the outlet 5.

In a shell-and-tube heat exchanger, in order to increase heat transfer efficiency, it is necessary to appropriately determine the number of times the fluid passes through the chamber in one direction toward the shell side or toward the body, and this number of passes is called the number of circulations (passes). Second
The figure shows an example of the arrangement of the tube-side partition plates for obtaining each number of passes of the fluid in the tubes of the multi-tubular heat exchanger shown in FIG.

In this conventional multi-tube heat exchanger, if the viscosity of the fluid in the tubes is low and the viscosity does not change significantly with changes in temperature or shear force, there is no problem with drifting and the loss per torque is small. However, if the fluid is highly viscous and its viscosity changes significantly with changes in temperature or shearing force, the following problems will occur.

When cooling the fluid in the tube, the amount of cooling heat transfer is determined by the residence time of the fluid in the tube, so the slower the speed of the fluid in the tube, the better the cooling.

For fluids whose viscosity increases significantly as the temperature decreases,
Due to the increased viscosity of the cooled fluid in the pipes, the flow resistance increases and the flow velocity decreases, and if the flow velocity becomes low r, it is further cooled, and as a result, the pressure balance in the tube group cannot be maintained, and only some of the tubes are There is a drawback that the fluid does not flow, which causes a biased flow.

Conversely, when heating 11/counterfluid, use 1-A of 1-1 temperature.
At the same time, for fluids with low viscosity, the viscosity of the heated fluid in the pipes decreases, and when shearing force is applied, the viscosity decrease further increases, making it impossible to maintain pressure balance in the tube group. However, it still has the disadvantage of causing drift.

The uninvented device is used when a fluid whose viscosity changes dramatically with changes in temperature or shear force is heated or cooled using a shell-and-tube heat exchanger, and when this method is used as a reactor to perform a reaction such as a polymerization reaction. Its purpose is to eliminate the defects listed in L that occur in conventional heat exchangers when
In the heat exchanger according to the present invention, a plurality of heat exchanger tube groups are arranged within the main body, and the flow path directions of the tube groups intersect! It is characterized in that a plurality of different concentric buses are formed in f, and the illustrated cross-sectional area of the heat exchanger tubes of each bus sequentially decreases or increases. The heat exchanger tube group is arranged in parallel between the flange on the person 1'' side and the flange on the exit 11 side.

A pivot-shaped groove or something equivalent to a groove is formed on the flange on the person 1-1 side and the flange on the side 1-1. The inner group of tubes and the group of tubes just outside thereof are sequentially communicated through one groove formed in a concentric shape.

Is the fluid to be heat exchanged flowing in from the tube group inside the green tube directly outside through the groove formed in the flange? 180 to 61Y
6 inverted and flows into the outer tube group through the groove formed in the opposing flange.

The heat medium flowing in from another inlet passes between these tube groups and flows out from another outlet.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 shows an embodiment of a multi-tube heat exchanger for cooling fluid within the tubes.

The fluid to be cooled enters only from a certain number of tubes 2a in a part of the brass tubes with reference to the center of the tubes on the person 1 side (
l bus), the fluid flowing out from the outlet side tube group 2a is 180
°The outer periphery of the tube group 2a of which the number of tubes a is larger in a certain proportion than the number of tube groups 2a from which the fluid has flowed out (in the case of heating the fluid in the tube, the number is smaller in a certain proportion, the same shall apply hereinafter). Tube group 2
The fluid enters b (2 passes) and increases in size by 1 on the person 1-11 side, then reverses 180° again and enters the outer circumferential pipes of compensation group 2b, the number of which is larger at a certain rate than the number of pipes g2b from which the fluid has flowed out. Enters group 2c (3 passes) Outflows from [13].

Although three passes are shown in this example, it is possible to increase the number of passes to an appropriate number such as four passes or five passes.

On the other hand, the heat medium flows in from the population 4 and flows out from the outlet 1'5.

Figure 4 shows the shell-and-tube heat exchanger shown in Figure 3? 6. Inflow and outflow of counter-fluids ``1.1.

Seal 8 of side flange 7 on side flange 6 and 11
The array may be a concentric polygon array or a concentric circle array.

Seal 8.9 uses an O-ring in this example, and
1, exit 1” side number crossing! Finish by inserting the O-ring into the O-ring groove on L! , II to obtain a predetermined number of passes.

FIG. 5 is a sectional view and a view taken in the direction of arrow A of a shell-and-tube heat exchanger according to another embodiment of the cutting method.

In this example, the sole method using full force skates io and ti is also possible, as in the case of 7+bus.

FIG. 6 is a sectional view of an embodiment of a multi-tube heat exchanger for heating fluid within the tubes.

The functions and effects of the wooden invention will be explained below.

When cooling -11 Newton fluids such as tomato hese or miso, the viscosity increases rapidly when the cutting speed and temperature are low. self is generated and cannot be cooled to a predetermined temperature.

According to the device of the present invention, the high temperature and low viscosity fluid passes through the group of l busses 11, so the flow velocity is not reduced and the residence time in the pipe is not increased, so there is less uneven cooling and no uneven flow. Occurrence is prevented.

Furthermore, since the shear rate increases, the viscosity is further reduced, and an increase in pressure loss can also be suppressed.

The fluid that has flowed out of the first pass tube group on the outlet side is reversed 1806 and flows into the second pass tube group.

The viscosity of the fluid inside the tubes decreases by the amount of cooling and lower temperature in the first pass, but the viscosity of the fluid in the tubes decreases by the amount of cooling, but the viscosity of the fluid in the tubes in the second pass 1 is lower than that in the first pass [J]. Since the ratio increases, the flow rate slows down and an increase in pressure loss can be suppressed.

Furthermore, uneven cooling is reduced and the occurrence of drifting is also prevented.

In this way, cooling is performed step by step through 1st pass, 2nd pass, 3rd pass, etc. to the extent that drifting does not occur, and the number of pipes passing through each path group, that is, the cross-sectional area, increases accordingly. Therefore, the fluid can be cooled to a predetermined temperature while preventing an increase in pressure loss.

, 11 Even when heating a body with 1 ton of l≦L, the number of tubes in the group is sequentially reduced by careful passes, the flow velocity of the fluid in the tubes is increased step by step, and the viscosity is lowered to prevent the occurrence of uneven flow.
- to do.

Also, conventional heat exchangers are used for polymerization reactions of polymers such as polystyrene. When used as a K-type reactor, as the reaction progresses, the viscosity of the liquid becomes extremely high, and even the slightest unevenness of reaction causes uneven flow, which often prevents the desired reaction from taking place. In the apparatus according to the above, the viscosity does not become extremely high and drifting is difficult to occur, so the reaction proceeds uniformly.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of an example of a conventional shell-and-tube heat exchanger, Figure 2 is a directional view showing an example of the arrangement of the tube-side partition plates of the shell-and-tube heat exchanger shown in Figure @1, and Figure 3. 4 is a cross-sectional view of a multi-tubular heat exchanger according to an embodiment of the present invention in the case of cooling fluid in the tubes, and FIG. 4 is a view of arrows showing a method of partitioning the inlet and outlet of the fluid in the tubes of the multi-tubular heat exchanger of FIG. 3. Figure 5 is a sectional view and an arrow view of a shell-and-tube heat exchanger showing an embodiment of another partitioning method, and Figure 6 is a shell-and-tube heat exchanger according to an embodiment of the present invention when heating fluid in the pipes. FIG. 3 is a cross-sectional view of the exchanger. 2a, 2b, 2c, . . . The number of heat exchanger tubes that are larger at a certain rate is smaller. 8.9 . 1. ,,, O-ring 10, l l ,,,, Gasket applicant Noritake Company Limited agent] Asamichi Kato, Physician, Figure 1, Notification 21, Figure 3 @ Figure 4 h'> Figure 5 Ini 6 Figure

Claims (1)

[Claims] A plurality of heat exchanger tube groups are arranged in the heat exchanger body, and a plurality of concentric paths are carved with different flow directions of the bone tube group at the intersection IJ, and the assembly structure of the heat exchanger tubes in each path is... A heat exchanger characterized by a sequential decrease or increase.